#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define all(a) a.begin(), a.end()
const int mod = 998244353;
const int N = 1e5;
pair<int, int> chmax(pair<int, int> A, pair<int, int> B){
if(A.ff > B.ff) return A;
return B;
}
pair<int, int> chmin(pair<int, int> A, pair<int, int> B){
if(A.ff > B.ff) return B;
return A;
}
struct sparse{
vector<vector<pair<int, int> > > m_table;
vector<vector<pair<int, int> > > ma_table;
int n;
sparse(int sz){
n = sz;
m_table.resize(18);
ma_table.resize(18);
for(auto &i : m_table){
i.resize(sz);
}
for(auto &i : ma_table) i.resize(sz);
};
void build(vector<pair<int, int>> &a){
for(int lg = 0; lg < 18; lg++){
for(int i = 0;i < n; i++){
if(lg == 0){
m_table[lg][i] = a[i];
ma_table[lg][i] = a[i];
}else{
int k = 1<<(lg-1);
m_table[lg][i] = chmin(m_table[lg-1][i], m_table[lg-1][min(n - 1, i + k)]);
ma_table[lg][i] = chmax(ma_table[lg-1][i], ma_table[lg-1][min(n - 1, i + k)]);
}
}
}
}
pair<int, int> get_max(int l, int r){
int k = __lg(r-l+1);
return chmax(ma_table[k][l], ma_table[k][r-(1<<k) + 1]);
}
pair<int, int> get_min(int l, int r){
int k = __lg(r-l+1);
return chmin(m_table[k][l], m_table[k][r-(1<<k) + 1]);
}
};
vector<int> g[N+1];
int depth[N+1], c[N+1];
int timer=1;
int tin[N+1], tout[N+1];
int up[N+1][18];
int n, m, q;
void dfs(int v, int par){
up[v][0] = par;
tin[v] = timer++;
for(int i = 1;i < 18; i++){
up[v][i] = up[up[v][i-1]][i-1];
}
for(int to : g[v]){
if(to == par) continue;
depth[to] = depth[v] + 1;
dfs(to, v);
}
tout[v] = timer++;
}
int lca(int a, int b){
if(depth[a] > depth[b]) swap(a, b);
int k = depth[b] - depth[a];
for(int i = 0;i < 18; i++){
if(k & (1<<i)){
b = up[b][i];
}
}
if(a == b) return a;
for(int i = 17; i >= 0; i--){
if(up[a][i] != up[b][i]){
a = up[a][i];
b = up[b][i];
}
}
return up[a][0];
}
int vert;
vector<int> vec;
int in_subtree(int v){
int it = lower_bound(all(vec), tin[v]) - vec.begin();
if(it < (int)vec.size() && vec[it] <= tout[v]) return 1;
return 0;
}
void ans(int v, int par){
if(!in_subtree(v)) return;
vert++;
for(int to : g[v]){
if(to == par) continue;
ans(to, v);
}
}
signed main(){
ios::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin >> n >> m >> q;
int bambo = 1;
for(int i = 1;i < n; i++){
int a, b; cin >> a >> b;
if(a != i || b != a+1) bambo = 0;
g[a].push_back(b);
g[b].push_back(a);
}
for(int i = 0;i < m; i++){
cin >> c[i];
}
dfs(1, 1);
vector<pair<int, int> > vals;
for(int i = 0;i < m; i++){
vals.push_back(make_pair(tin[c[i]], c[i]));
}
sparse table(m);
table.build(vals);
if(bambo){
while(q--){
int l, r; cin >> l >> r;
l--, r--;
int mn = table.get_min(l, r).ss;
int mx = table.get_max(l, r).ss;
cout << depth[mx] - depth[mn] + 1 << '\n';
}
return 0;
}
while(q--){
int l, r; cin >> l >> r;
l--, r--;
int mn = c[l], mx = c[l];
vec.clear();
for(int i = l;i <= r; i++){
vec.push_back(tin[c[i]]);
if(tin[mn] > tin[c[i]]){
mn = c[i];
}
if(tin[mx] < tin[c[i]]){
mx = c[i];
}
}
mn = table.get_min(l, r).ss;
mx = table.get_max(l, r).ss;
sort(all(vec));
vec.erase(unique(all(vec)), vec.end());
vert = 0;
int lc = lca(mn, mx);
ans(lc, up[lc][0]);
cout << vert << '\n';
}
return 0;
}
